Notwithstanding the provisions of any other law, any person holding such a position who, without the lawful approval of his superior, fails to report for duty or otherwise absents himself from his position or abstains, in whole or in part, from the full, faithful and proper performance of his position shall be deemed on strike: Provided, That such person, upon request, shall be entitled to establish that he did not violate the provisions of this act. Such request must be filed in writing within ten days after regular compensation of such employe has ceased. In the case of a public employe who is entitled by law to a hearing upon dismissal or removal, such written request shall be filed with the officer or body having power to remove such employe, and such officer or body shall within ten days conduct a hearing to determine whether the provisions of this act have been violated by such public employe in the manner provided by law, appropriate to a proceeding to dismiss or remove such public employe. In the case of a public employe who is not entitled by law to a hearing upon dismissal or removal, the request for a hearing shall be filed with the Pennsylvania Labor Relations Board which shall, within ten days, conduct a hearing to determine whether the provisions of this act have been violated by such public employe in the manner provided for hearings before the board by the Pennsylvania Labor Relations Act.¹ All such proceedings shall be undertaken without unnecessary delay.